There are only official system requirements on the site which are released by developers or an official publisher.

Minimum system requirements:

Recommended system requirements:

CPU:

Pentium 4 or equivalent 1.7 GHz

CPU:

Pentium 4 or equivalent 2.4GHz

RAM:

512 MB

RAM:

1 GB

GPU:

A video card with 64 MB memory and one of these chipsets is required:
NVIDIA GeForce3 / NVIDIA GeForce4 (Ti series only) / ATI Radeon 8500.
Laptop versions of these chipsets may work but are not supported.

GPU:

128MB DirectX 9.0c compatible video card (NVIDIA Geforce 6800+/ATI Radeon 9800+)
Laptop versions of these chipsets may work but are not supported.